NPK Breakdown

NPK Breakdown

When you buy nutrients, soils, or supplements for your plants you will almost always see the NPK ratio right on the label.

NPK is the ratio of nitrogen, phosphorus, and potassium in a solution. It is important to know what role each of these elements play in plant development, and how to prevent deficiencies or overfeeding.


Nitrogen (N)

Other than being one of the top three nutrients for plants growth, nitrogen (N) may be the most important. Nitrogen is directly responsible for chlorophyll production as well as creating amino acids. It is also essential to photosynthesis.

Nitrogen deficiencies are one of the most common nutrient deficiencies that you might have to deal with. It becomes noticeable in the lower leaves as they turn a pale green. Eventually the leaves will yellow and die, and the deficiency will spread up the plant from the tips of the leaves inward.

It’s difficult to overuse nitrogen during the vegetative stage as the plants need it more during their growth. However if too much nitrogen is used in the flower stages, plants will continue to grow and stretch instead of focusing on flowering, leaving you with less dense and filled out flowers.

Phosphorus (P)

Phosphorus (P) is essential to early stage root development, stem strength, nutrient uptake, yield, resistance to disease and flower formation. Suffice to say it’s pretty important.

A catalyst for photosynthesis, plant metabolism and nutrient uptake, P acts as support for important biochemical reactions. The structures generated by photosynthesis, ATP (adenosine triphosphate) and ADP (adenosine diphosphate), contain high amounts of P that drive biochemical reactions and facilitates cell division.

Stunted growth and leaf discoloration are just a couple signs of P deficiency in your plants. Overtime, much like nitrogen, these symptoms will spread until the entire plant is effectively dead.

Overuse of P can lead to serious nutrient lockout. Elements like calcium, copper, iron, magnesium and zinc can all be blocked out by excess P. Once the issue is traced back to excess P, the plants need to be flushed with water thoroughly to break down the excess salt buildup.

Potassium (K)

While not as essential to plant tissue growth directly as nitrogen and phosphorous, Potassium (K) acts a catalyzer similar to phosphorous. It takes part in photosynthesis, production of proteins and amino acids in which it interacts with nitrogen, improves root systems in conjunction with phosphorous, and so on.

Potassium deficiency makes itself known over time, starting with older leaves and working into the younger ones. Yellowing tips that progress toward the center of your leaves, weak stems and lower disease resistance are some of the visible symptoms. If you have too much calcium, it can cause a nutrient block of K, leading to an inadvertent deficiency.

Conversely, too much K can block calcium, magnesium, zinc and iron from being absorbed by the plant. Like P, these nutrient blocks can cause all of their own problems, and the best way to deal with too much K is to flush your plant with fresh water until all blockage and solvents are dissolved.

It’s important to pay attention to these details when buying your nutrients. There are specific NPK ratios for early stages of growth, all the way to up the flowering stages. These specific ratios will cater to the specific NPK needs of your plant during its specific stage of growth. Come into Cultivate today and let us help you find the best nutrients for your plants.

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